Assessing the quality of age reporting at a time of general data quality improvement: going beyond the original Whipple's index

Thomas Spoorenberg, United Nations

With the improvement of age reports the classical attractions on 0 and 5 age digit are fading, the widely and traditionally used Whipple's index does not offer anymore a fair and reliable measure to assess the quality of age reporting. Demographers have to propose new ways to measure the quality of age reporting. The total modified Whipple's index (Wtot) recently introduced offers such alternative (Spoorenberg, 2007). The quality of age reporting computed from these two indices (original Whipple's index and Wtot) on 234 census single-year of age returns from 145 countries are here compared. The main results show that, as expected, the original Whipple's index does not account well for the quality of age reporting once it is improving and reaches better levels. The total modified Whipple's index (Wtot) offers however a simple alternative which fully accounts for the changes in the attraction/repulsion on all age-digits.